Scotland's economy secretary has said the Conservative government should indicate whether it wants the UK to stay in the single market after Brexit.
Keith Brown believes it is "untenable" to maintain silence on the issue.
He was speaking six months on from June's referendum which saw UK voters back leaving the European Union.
In response to Mr Brown's call, a UK government spokeswoman said the United Kingdom would "continue to be a global leader of free trade".
She added that it would also remain the "best place in Europe to run and grow a business".
Mr Brown would like to see assurances given that Scotland's interests would be at the heart of Brexit negotiations.
He reckoned that coming out of the single market would "severely damage" the economy in Scotland.
But she also said it would be possible for Scotland to remain in the free trade bloc even if the rest of the UK left.
The UK government said it was committed to involving each of the devolved administrations in Scotland, Wales and Northern Ireland, but that a special deal for Scotland was unrealistic.
Mr Brown said a different deal north of the border should be considered because life outside the single market could cost Scotland 80,000 jobs over 10 years.
The minister explained: "Independent research has estimated the cost of leaving the single market at more than £11bn annually which could mean Scotland's public services revenues would be £3.7bn per year lower than they are now.
"The EU is also the main destination market for Scotland's international exports, accounting for 42% of trade in 2014.
"Losing membership of the world's largest single market would mean forfeiting the right to buy goods and services from other parts of this union free from import taxes and would also seriously impact on the ability of Scottish companies to export to other EU member nations.
"More than six months on from the EU referendum, it is completely untenable that the UK government are unable to give even an indicative position on whether it supports remaining in the single market."
What is the EU's single market?
- In the early 1990s the European common market grew into the single market we know today.
- At its heart is a free trade area, which is a market where there are no tariffs or taxes on trade between countries. While its members can trade freely with each other, they also impose common tariffs on imports from non-EU countries.
- Being a member of the single market means a country gets the benefit of any trade deal struck between the EU and other countries - the flip side is that member states cannot set their own tariffs.
- The free movement rules also apply to people and capital as well as goods.
- Most countries in the single market also have a single currency - the euro - but the UK did not adopt it.
Although the UK as a whole voted to leave the EU by 52% to 48%, voters in Scotland backed remain by 62% to 38%.
Mr Brown added: "The people of Scotland voted to remain within the EU and a 'hard Brexit' would severely damage our economic and social interests.
"That is why I want an assurance from the UK government that Scotland's interests will be at the heart of any negotiations on the future of the UK within the EU."
The UK government spokeswoman said that the UK as a whole had voted to leave the EU.
She added: "The prime minister has repeatedly made clear that we want to ensure British companies have the maximum freedom to trade with and operate in the single market.
"We are determined that the UK will continue to be a global leader of free trade and that it will remain the best place in Europe to run and grow a business."